Aerosol valve and sprayhead

ABSTRACT

An aerosol spray valve of the type which utilizes a reciprocable plunger moving within a valve housing that is in turn mounted to a cover member. The cover member is adapted to be crimped to a canister and has a dip tube extending from the interior of the valve housing to the bottom of the canister. Pressurized product is forced from the interior of the canister through the dip tube into the valve housing and out of the cover member through a central hole into a sprayhead that is mounted in the hole. An annular elastomeric gasket surrounds the hole and the upper end of the reciprocable plunger forms a valve seat that is springbiased against the underside of the gasket to prevent pressurized product from emerging. The sprayhead has an associated stem that enters a socket formed in the plunger, the stem being slidably and sealingly engaged through the hole and the passageway in the elastomeric gasket. The stem is imperforate. The socket of the plunger has channel means formed in its interior wall along the vertical length thereof so that there are one or more passageways formed between the outer surface of the stem and the socket to transport the pressurized product. The pressurized product enters at the top of the plunger when the valve seat is unseated from the elastomeric gasket, passing through the passageways to the bottom of the plunger on the interior thereof, and then into the hollow bore of the stem from whence it is conveyed to the button of the sprayhead and out to the atmosphere when the button is depressed. The bottom end of the stem is spaced above the bottom floor of the socket by reason of a shoulder formed on the stem where it enters the socket. The stem may be separable from the button of the sprayhead or may be integral therewith. If separable, the stem is substantially permanently engaged in the socket. The resulting structure provides accurate metering of the pressurized product.

United States Patent 1191 Green Aug. 20, 1974 AEROSOL VALVE ANDSPRAYHEAD a dip tube extending from the interior of the valve [76]mentor: Edward Green 11 Army Trail housing to the bottom of thecanister. Pressurized Rd Addison [IL 60101 product 1s forced from the1nter1or of the canister through the dip tube into the valve housing andout of Filedi 1971 the cover member through a central hole into asprayhead that is mounted in the hole. An annular elasto- [21] Appl'124309 meric gasket surrounds the hole and the upper end of thereciprocable plunger forms a valve seat that is [52] US. Cl. ZZZ/402.24spring-biased against the underside of the gasket to [51] Int. Cl B65d83/14 prevent pressurized product from emerging. The Field Of Search222/4 sprayhead has an associated stem that enters a socket 222/402- 3,39 1/353, 354 formed in the plunger, the stem being slidably andsealingly engaged through the hole and the passage- [56] ReferencesCited way in the elastomeric gasket. The stem is imperfo- UNITED STATESPATENTS rate. The socket of the plunger has channel means 2,913,15411/1959 Kuffer 222/402.24 x formed in its interior wall along verticallength 3,074,601 1/1963 Kuffer 222/40224 thereof 80 that there are oneOr more passageways 3,098,589 7/1963 Graham 251/353 X formed between theouter surface of the stem and the 3,145,011 8/1964 Kappel.... ZZZ/402.24X socket to transport the pressurized product. The pres- 3. 66, 5 1/1965appel..-. 222/ X surized product enters at the top of the plunger when3,589,57l 6/1971 Green ZZZ/402.24 the valve eat is unsealed from theelastomeric gasket FOREIGN PATENTS 0 APPLICATIONS passing through thepassageways to the bottom of the 606,457 7/1960 ltaly 251/353 Plungerthe interior thereof and F into the 1,244,457 9/1960 France 222 4022410W bore of the Stem from whence Primary ExaminerRobert B. ReevesAssistant Examiner.lohn P. Shannon Attorney, Agent, or Firm-PerryCarvellas, Esq.

[5 7 ABSTRACT the button of the sprayhead and out to the atmosphere whenthe button is depressed. The bottom end of the stem is spaced above thebottom floor of the socket by reason of a shoulder formed on the stemwhere it enters the socket. The stem may be separable from the button ofthe sprayhead or may be integral therewith. lf separable, the stem issubstantially permanently engaged in the socket. The resulting structureprovides accurate metering of the pressurized product.

5 Claims, 12 Drawing Figures PATENTEDMIEZOW 1 3, 30,412

- SHEET 2B? 2 I 1 [INVENTOR 5W1 ATTORNEYS C ROSS-REFERENCE TO RELATEDAPPLICATION The invention herein is a modification of the inventiondisclosed and claimed in a copending application having the same titleas the application herein, Ser. No. 128,404, filed on or about Mar. 26,1971, now US. Pat. No. 3,7l5,08l.

BACKGROUND OF THE INVENTION The invention herein relates to aerosolvalves and more particularly is concerned with a novel valveconstruction for a pressurized package in which the metering of thepressurized product remains constant for the life of the package and maybe accurately established at the time of the manufacture of the valve.

The background of the invention herein is substantially the same as thatof the copending application, and reference may be had to said copendingapplication for the total details thereof. For the purposes of thisapplication, however, so much of the background as neededto appreciateand understand the invention will be repeated to some extent.

The invention herein is applicable to two principaltypes of aerosolvalve constructions, namely, those in which the sprayhead whichcomprises a stem and button are integral and are removable from thepackage, and those in which the stem is substantially permanentlysecured to the valve assembly and the button is removable from the stem.The basic structure of the removable integral sprayhead is taught in US.Pat. No. 2,777,735. Stem valves are disclosed in US. Pat. Nos. 3,266,678and 3,348,743 although the invention herein and that of the copendingapplication teach stem valve structures which are much simpler thanthose of the patents.

As explained in the copending application, problems of maintaining themetering of the pressurized product were attempted to be solved by thestructures of US. Pat. Nos. 3,045,877 and 3,233,792. These problemsconsisted of a closing of the metering slot in the stem of the sprayheadof the integral type due to constriction by the elastomeric gasket usedin the valve assembly, and a closing of said slot because of swelling ofthe plastic from which the sprayhead was made.

According to the teachings of the copending application, the metering ofvalve assemblies of the general types involved was established by meansof channels formed on the interior of the wall of the socket of thevalve plunger into which the stem is engaged. In this manner, manyadvantages accrue, including a. the sprayhead is made with the stemimperforate except for the axial end opening at the bottom of the stem,hence only one sprayhead design is needed for all packages irrespectiveof the metering desired; b. since the sprayhead stem carries no preciseslots or side holes (as in the case of most known stem valves) thesprayhead can be made of the socalled soft plastics such as polyethyleneinstead of the socalled rigid plastics such as nylon, the latter beingmore expensive than the former; in the case of sprayheads which areformed of permanently mounted stems and removable buttons, at least thebuttons can be made of the economical soft plastic;

0. the expense of making the sprayheads, whether integral or two-pieceis less than formerly because of the elimination of the complex diesneeded to make sprayheads whose stems have metering slots or holes;

(1. since the metering channels are in the valve plunger which is alarger piece than the stem, and in addition are fully backed up by thebody of the plunger, the channels are not likely to change dimensionsfrom any cause and tend to maintain the accuracy of their metering forthe full life of the pressurized package; and

e. the molds for the molding of the valve plunger with the channels onthe interior thereof are simpler and hence more economical to make andmaintain than the type of molds used to make the sprayheads whose stemshad slots or holes for metering.

In the copending application, the transportation of the pressurizedproduct fromthe valve chamber to the hollow bore of the stem wasaccomplished in several manners. In one type of construction, the axialend of the stem bottoms in the socket of the valve plunger and engagesagainst the floor thereof and in order to enable the pressurized productto pass the wall of the stem, grooves are formed in the floor extendingfrom the bottom ends of the channels below the floor to the opening inthe axial end of the stem. In such structure, if there is a post, suchas for example of the type used for gassing packages having integralsprayheads'as taught in U.S. Pat. No. 3,386,479, the diameter of thepost is less than the internal diameter of the bottom end of the bore ofthe stem to permit pressurized product to pass from the grooves up thebore. In the case there is no post, the grooves are only required tocarry the pressurized product past the stem wall to the bore directly.In another type of construction, the channels ended at the floor and thestem was supported by ridges or footings in the bottom of the socket tospace the stem end above the floor and thereby permit passage of thepressurized product to the bore.

The copending application likewise taught application of the basicinvention to valve plungers with and without galleries. In the case ofthose with galleries, the upper ends of the channels opened to thegalleries, while in the case of those without galleries, the upper endsof the channels opened at the valve seat. The invention herein is alsoapplicable to these types of structures.

The invention herein solves the problem of spacing the stem above thefloor by means of structure which is an integral part of the stem, butwithout complicating the manufacture of the stem or giving up commonadvantages of the invention of said copending application. In addition,since the spacing of the stem above the floor of the socket does notdepend upon any engagement of the axial end of the stem with the flooror footings or ridges in the bottom of the socket, the presence of flashoccurring on the bottom end of the stem during molding has no effectupon metering or stability of the stem in the socket. In some priorstructures, flash -on the stem end was intolerable because the perfectseating of the stem end in the socket was required to establish desiredmetering.

SUMMARY OF THE INVENTION According to the invention herein, the stem ofthe sprayhead is made with the portion that enters the socket ofslightly smaller diameter than the remainder of the stem whereby to forma shoulder. The length of the portion which enters the socket is made tohave an axial length somewhat less than the depth of the socket from thepoint at which the shoulder engages the upper end of the socket to itsfloor so that when fully seated in the socket the axial end of the stemis spaced above the floor. In this way, the channels in the innersurface of the valve plunger wall need not extend below the floor andthere is no need for grooves in the floor. The shoulder of the sternrests either on the valve seat in the case of a valve plunger that hasno gallery, or on the gallery of a valve seat which has a gallery. Themetering is controlled by the total of the smallest cross-sectionalareas of the respective channel entrances formed by the stem at theupper ends of the channels.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a fragmentary elevationalview of the upper end of a pressurized package of the type in connectionwith which the invention is used;

FIG. 2 is a fragmentary median sectional view taken through the packageof FIG. I along the line 2-2 and in the indicated direction, the valveconstruction including a removable sprayhead;

FIG. 3 is a sectional view taken generally along the line 33 of FIG. 2and in the indicated direction;

FIG. 4 is a fragmentary view on an enlarged scale of a portion of FIG.2, illustrating the relationship of the parts during the time that thesprayhead has been depressed and pressurized product is being dispensed;

FIG. 5 is a top plan view of the valve plunger illustrated in FIGS. 2,3, and 4;

FIG. 6 is a' sectional view through the valve plunger of FIG. 5 takenalong the line 6-6 and in the indicated direction;

FIG. 7 is a fragmentary sectional view taken along the line 7-7 of FIG.6 and in the indicated direction;

FIG. 8 is a fragmentary sectional view taken generally along the line 88 of FIG. 4 and in the indicated direction;

FIG. 9 is a view similar to that of FIG. 6 but showing the invention asapplied to a structure in which the valve plunger does not have agallery, the bottom of a stem being shown partially in elevation andpartially in section;

FIG. 10 is a fragmentary sectional view taken generally along the line10I0 of FIG. 9 and in the indicated direction;

FIG. 11 is a side elevational view of a sprayhead of the constructionfor use with the invention in which the button and stem are integral;and

FIG. 12 is an exploded elevational view of a sprayhead of theconstruction for use with the invention in which the button and stem areseparate articles.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention is applicable toeither the stem valve type of structure or to the structure in whichtheentire sprayhead is removable in the manner taught by U.S. Pat. No.2,777,735. Likewise, it will be seen that the invention is applicable tostructures which use a gallery and those which do not.

In FIGS. 1 through 8 there is illustrated a type of valve constructionin which the sprayhead is fully removable, there is a gallery in theupper end of the wall of the valve plunger, and in which there is aplastic valve housing.

In FIGS. 1 through 8 there is illustrated a type of valve constructionin which the sprayhead is fully removable, there is a gallery in theupper end of the wall of the valve plunger, and in which there is aplastic valve housing.

The valve assembly of the invention is designated by the referencecharacter 20. This valve assembly 20 is purchased by the tiller who putsit together with a canister 22 to make up the pressurized package,filling it with the propellant either before or after he installs thesprayhead or spray button, depending upon his techniques. FIG. 1 shows acanister 22 which has a cylindrical body 24 that is held to a metalpressure dome 26 by a locked and sealed seam 28. The upper end of thedome 26 provides an opening or mouth 30 that has a rolled or curledformation 32. The valve assembly 20 is adapted to be mounted in theopening 30 and crimped in place as by the crimp 34, the seal beingeffected by the joint to be described.

The valve assembly 20 includes a metal cover member 36 that has anannular well 38 that surrounds an upstanding central boss 40 that isintegral with the floor of the well and is formed from the same integralsheet metal member that constitutes the cover member 36. The upper edgeof the cover member 36 is rolled as shown at 42 and this rolled edgeengages over the rolled formation 32 surrounding the mouth 30 of thedome 26. A layer of gasketing material 44 between the rolled edges sealsthe cover member 36 into the opening 30 of the canister 22. v

The valve assembly 20 includes a valve housing 46 which is often calledan eyelet in the trade, this housing in the structure being describedbeing made out of some suitable plastic and having its upper end flaredor enlarged to provide the flange 48 that engages into the boss 40 andis locked in place by means of the crimps 50. A disc-like elastomericgasket 52 is compressed by the flange 48 against the inside of the upperwall 54 of the boss 40 so that the gasket 52 is sandwiched between theflange 48 and the upper wall 54. The upper wall 54 of the boss 40 has acentral opening 56 and the gasket 52 likewise has a central passageway58 that is aligned with the opening 56.

On its interior, the valve housing 46 provides a chamber 60 into whichpressurized product is adapted to be introduced by way of the dip tube62 that is locked to the bottom end of the housing 46 by any suitablemeans such as the split locking collar 64. The exact construction ofthis locking means is described in U.S. Pat. No. 3,159,318. Any othermethod of securing the dip tube 62 may be used. In the chamber 60 thereis a valve plunger 66 which provides a shoulder 68 and pilot projections70 to seat a helical spring 72 that urges the plunger 66 upwardly asviewed, against the bottom surface of the gasket 52. The interior, ofthe plunger 66 provides a socket 74 which has a blind bottom end whichforms a floor 76, as best seen in FIGS. 4 to 6.

The upper end of the socket 74 has a gallery 78 that extends around theinterior thereof, giving rise to a narrow section 80 that has an endsurface 82. This end surface 82 is that which engages tightly againstthe bottom surface of the elastomeric gasket 52 as best seen in FIG. 2and comprises the valve seat. When the valve plunger 66 moves off thegasket 52 as by being pushed downwardly, pressurized product from thechamber 60 will pass over the seat 82 and into the gallery 78, as bestshown in FIG. 4. The interior of the socket 74 has channels 84 and 86formed therein, these channels opening at their upper ends into thegallery 78 and extending to the floor 76 at their bottom ends. Thechannels 84 and 86 extend generally axially of the valve plunger asviewed, for example, in FIGS. 4 and 6. The floor 76 is flat except forthe post 92 in its center, this post being integral with the valveplunger 66 and extending upwardly from the floor.

A sprayhead 94 is mounted in association with the valve assembly 20, thesprayhead comprising a button 96 with an integral, hollow bore stem 98depending from the bottom of the button. The stem has a centralexpansion chamber 100 which leads to a transverse passageway 102 in thebutton 96 connecting the external spray orifice 104 with the saidchamber 100. The bottom end of the stem 98 has a slight chamfer at 106as shown in FIG. 4 to assist in guiding the stem through the gasket 52and into the socket 74 when the sprayhead 94 is assembled to the valveassembly 20. At its bottom end, the interior hollow chamber 100 is ofsuch diameter that it clears the post 92 on the interior of the stem bya substantial amount, as best seen in FIGS. v3 and 4.

As for its exterior dimensions and configuration, therein the structureof this invention differs from that of the copending application thusgiving'rise to the ad'- vantages which are ascribed to this invention.The diameter of the stem 98 above the portion 99 which fits into thesocket 74 is slightly larger than the said portion 99 so that the effectis the formation of an annular shoulder 101 on the stem 98. This is bestseen in FIGS. 4 and 11. The exterior dimension of the lower end 99 ofthe stem 98 is such as to provide a relatively tight sliding fit withthe socket 74. In this manner, since the stem 98 is imperforate alongits entire length'including the lower portion 99 except for the openingto the chamber 100 at the bottom axial end, no pressurized product canescape from the valve chamber 60 except by way of the channels 84 and 86and the bore 100 of the stem 98.

The diameter of the stem 98 above the shoulder 101 is somewhat less thanthe largest diameter of the gallery 78 so that, although the shoulderoverlaps the gallery a slight amount as may be ascertained by examiningFIG. 8, it does not extend to the narrow section 80. This leaves a spaceindicated at 103 in FIG. 8 which slightly narrows the gallery 78. Sincethe channels 84 and 86 open into the gallery at their upper ends, theentrances to the channels are also-slightly narrowed, also as shown inFIG. 8. These entrances are seen to be the smallest cross sections forthe flow of pressurized prod uct to the bore 100 from the chamber 60,and hence the cross-sectional dimensions of these entrances control themetering of the valve assembly 20, assuming that none of the remainderof the passageways such as 102 and the orifice 104 has a smaller totalcross section. The cross-sectional area of one such entrance multipliedby the number of channels gives the total cross-sectional areacontrolling metering. Increasing the number of channels to more than twoor decreasing them to one enables the manufacturer to build any desiredmetering into the structure.

The axial distance from the shoulder 101 to the axial end 105 of thestem 98 is chosen to be somewhat less than the axial distance from thegallery 78 to the floor 76. In this manner, the shoulder 101 serves asstop means when the stem is inserted into the socket 74, preventing thesaid end 105 from engaging the floor 76. The end 105 is thus spacedabove the floor 76 so that pressurized product emerging from the bottomends of the channels 84 and 86 passes across the floor 76, upwardlyalongside the post 92 and into the bore of the stem.

In prior structures, the post 92 has served as an assist in guiding andseating the stem in the bottom of the socket, and in such cases, theouter diameter of the post was the same as the inner diameter of thebore of the stern. In this case, since it is required that there be aspace to enable the pressurized product to enter the lower end of theexpansion chamber 100 and move past the post 92, the outer diameter ofthe post 92 is substantially less than the inner diameter of the bore100. The primary purpose for the post in the construction which isillustrated is to enable gassing the pressurized package by theapparatus and method disclosed in US. Pat. No. 3,386,479. Otherwise, thepost 92 is not essential to the operation of the valve structure.

The operation of the aerosol valve of the invention is best described inconnection with FIGS. 2 and 4. In FIG. 2 the valve is closed, with thevalve seat 82 tightly pressed against the underside of the gasket 52.Under these circumstances no pressurized product can escape from thevalve chamber 60. The entire sprayhead 94 may be removed from the valveassembly 20 if desired without affecting the inoperative condition. Thisprovides certain advantages which are common with the construction ofthe valve structureof US. Pat. No. 2,777,735.

With the sprayhead 94 in place, when it is desired to dispense thepressurized product, the button 96 is pressed downwardly and theshoulder 101 engaging the gallery 78 of the valve plunger 66 forces theplunger downward against the bias of the spring 72 to the position whichis illustrated in FIG. 4. When this occurs, pressurized productgenerally follows the lines of the arrows illustrated in FIG. 4. Itrises in the chamber 60 to the top of the plunger 66, passes over thevalve seat 82 and into the gallery 78. From the gallery 78, thepressurized product passes down the channels 84 and 86 to the floor 76,across the floor and the axial end I of the stem portion 99 and past thepost 92, moving into the bore-100 of the stem 98. From the expansionchamber 100 the pressurized product passes to the atmosphere by way ofthe passageway 102 and the external orifice 104.

To discontinue the spraying of the aerosol product, the button 96 isreleased by the user and the sprayhead 94 moves upwardly because of thespring 72, thereby closing the valve due tothe valve seat 82 once moreengaging against the underside of the gasket 52.

While there are advantages in having a gallery as 78 in connection withthe apparatus, it is not essential to the operation of the invention andthe principal advantages are achieved without the use of the gallery.For example, in FIGS. 9 and 10 the gallery is omitted. In this case thevalve plunger is constructed in the same manner as the valve plunger 66of FIGS. 1

through 8, except that the channels 112 and 113 which are theequivalents of the channels 84 and 86, respectively, of the valveassembly 20 end at the valve seat 114. The valve seat 114 issubstantially wider than the valve seat 82, since it is formed by theupper end of the wall 116 which forms the socket 118 of the plunger 110.

In the structure of FIGS. 9 and 10, the stem 120 has the reduceddiameter lower portion 122 which provides the shoulder 125 that servesas stop means, engaging the valve seat 114 and partially overlapping thesame as seen in FIG. 10. This prevents the bottom axial end 126 of thestem portion 122 from touching the floor 128, the stem and thereby beingspaced above the floor 128. The structure of FIG. 9 does not include acentral post like the post 92, it being assumed that the post is notneeded for gassing. The stem 120 could be a stem which is not integralwith a button, as, for example, shown in FIG. 12. In such case, thebutton 130 could be made out of soft plastic of the polyethylene typewhile the stem 120 could be made out of rigid plastic of the nylon typesince it will be force fitted into the socket 1 18 to be substantiallypermanently engaged therein. Thus, without a post, the pressurizedproduct, passes from the bottom ends of the channels 112 and 113 acrossthe floor 128 and directly into the bore 132 of the stem.

In this latter case, the metering is established by the exposed upperentrances of the channels 112 and 113 since these are most likely to bethe areas of smallest cross-sectional dimension. The slight overlap. ofthe channel ends is not a disadvantage since the entrances open torelatively larger cross-sectionai areas and clogging in the channels isnot too likely to occur.

In both of the structures described above, the accumulation of residueat the bottom of the socket 74 or 118 is also not likely to interferewith the operation of the pressurized package.

Separable stem structures could be used in the valve assembly 20 to makethe same into a stem valve type of apparatus.

The embodiments of the invention may have many modifications withoutdeparting from the spirit or scope of the invention as defined in theappended claims,

What it is desired to secure by Letters Patent of the United States is:I v

1. A valve structure for a pressurizedpackage comprising:

A. a cover member adapted to package,

B. a housing connected to the bottom of the cover member and beingenclosed but for a first opening through the cover member and a secondopening be installed in said adapted to communicate with the interior ofthe package,

C. an elastomeric gasket between the housing and the cover member andhaving a passageway aligned with the first opening,

D. a valve plunger in the housing spring-biased against the-elastomericgasketand when so biased blocking passage of pressurized product fromthe interior of the housing to the exterior of the cover member, saidvalve plunger comprising;

1. a body having an outer cylindrical wall defining a central bottomfloor and an upwardly extending center post,

2. the cylindrical wall having a valve seat at its upper end around theupper entrance of the socket,

3. channel means in the interior of the socket in said wall extendinggenerally axially of the cylindrical wall, opening at the upper endthereof adjacent the valve seat and opening at the bottom end adjacentsaid floor,

E. a sprayhead including an exterior movable button having an externalorifice and a hollow cylindrical stem, said stem having an upper and alower portion, the upper portion of the stern passing through thepassageway of the elastomeric gasket in a sealing and siding engagement,said upper portion having an external diameter slightly greater than theinternal diameter of the socket Wall, the lower stern portiontelescopically and sealingly engaged in said socket, said lower portionbeing of slightly smaller diameter than the upper stem portion to form ashoulder, said shoulder engaging against the portion of the plungersurrounding the entrance to the socket to define metering entrance meansin cooperation with the upper end of said channel means, and the lowerstem portion having an axial end opening spaced away from the centerpost providing the only entrance to the interior of the hollow stem fromthe bottom end thereof and said lower portion having a length less thanthe depth of the socket, and

F. whereby the bottom of the upper stem portion engages the internalsocket wall to establish a pressurized product flow path from thehousing during actuation of the package, said path extending over saidvalve seat down through the channel means, between the floor and thebottom end of the stem and then up through the axial opening in the stembetween the internal wall of the stem and the post.

2. The valve structure as claimed in claim 1 including a gallery at theupper entrance of the socket below said valve seat into which gallerysaid channel means at the upper end thereof open,

3. A valve assembly adapted to be sealed to the open top of a canisterand adapted to have a sprayhead mounted therein, which valve assemblycomprises: a sprayhead having a push button and a stem connectedtogether, the stem extending into the valve assembly from theexteriorthereof, a cover member having a central passageway for movementof the stem therethrough, a gasket, a valve housing secured to theinside of the cover member, a valve plunger in the housing having avalve seat on the upper end thereof and being spring-biased upwardlyagainst the gasket, the valve plunger having an upwardly opening socketconfined by the valve seat, the gasket being sandwiched between thevalve housing and the cover member and having a centralpassagewaytherethrough aligned with the central passageway in the covermember, the socket being axially aligned with the passageways, the stemslidingly and sealingly passing through the central passageways into thesocket and engaged therein and having its exterior wall sealinglyengaged in said socket, means communicating between the interior of thevalve housing over the valve seat and the hollow bore of the stem, thelower end of the stem that is engaged in the socket being imperforatebut for an axial end opening, the plunger having axially extendingchannel means on the interiorof the socket opening at the upper endthereof adjacent the valve seat and extending to the bottom of thesocket and the stem having a shoulder cooperating with the valve plungerto space the lower end of the stem above the bottom of the socket, saidshoulder having an outer diameter greater than the inner diameter ofsaid socket and that portion of the stem which engages in said socket,the shoulder engaging against the portion of the plunger that surroundsthe entrance to the socket to define metering entrance means incooperation with the upper end of said channel means, the axial lengthof the portion of the stem which engages in the socket being less thanthe axial length of the Open.

1. A valve structure for a pressurized package comprising: A. a covermember adapted to be installed in said package, B. a housing connectedto the bottom of the cover member and being enclosed but for a firstopening through the cover member and a second opening adapted tocommunicate with the interior of the package, C. an elastomeric gasketbetween the housing and the cover member and having a passageway alignedwith the first opening, D. a valve plunger in the housing spring-biasedagainst the elastomeric gasket and when so biased blocking passage ofpressurized product from the interior of the housing to the exterior ofthe cover member, said valve plunger comprising;
 1. a body having anouter cylindrical wall defining a central bottom floor and an upwardlyextending center post,
 2. the cylindrical wall having a valve seat atits upper end around the upper entrance of the socket,
 3. channel meansin the interior of the socket in said wall extending generally axiallyof the cylindrical wall, opening at the upper end thereof adjacent thevalve seat and opening at the bottom end adjacent said floor, E. asprayhead including an exterior movable button having an externalorifice and a hollow cylindrical stem, said stem having an upper and alower portion, the upper portion of the stem passing through thepassageway of the elastomeric gasket in a sealing and siding engagement,said upper portion having an external diameter slightly greater than theinternal diameter of the socket wall, the lower stem portiontelescopically and sealingly engaged in said socket, said lower portionbeing of slightly smaller diameter than the upper stem portion to form ashoulder, said shoulder engaging against the portion of the plungersurrounding the entrance to the socket to define metering entrance meansin cooperation with the upper end of said channel means, and the lowerstem portion having an axial end opening spaced away from the centerpost providing the only entrance to the interior of the hollow stem fromthe bottom end thereof and said lower portion having a length less thanthe depth of the socket, and F. whereby the bottom of the upper stemportion engages the internal socket wall to establish a pressurizedproduct flow path from the housing during actuation of the package, saidpath extending over said valve seat down through the channel means,between the floor and the bottom end of the stem and then up through theaxial opening in the stem between the internal wall of the stem and thepost.
 2. the cylindrical wall having a valve seat at its upper endaround the upper entrance of the socket,
 2. The valve structure asclaimed in claim 1 including a gallery at the upper entrance of thesocket below said valve seat into which gallery said channel means atthe upper end thereof open,
 3. A valve assembly adapted to be sealed tothe open top of a canister and adapted to have a sprayhead mountedtherein, which valve assembly comprises: a sprayhead having a pushbutton and a stem connected together, the stem extending into the valveassembly from the exterior thereof, a cover member having a centralpassaGeway for movement of the stem therethrough, a gasket, a valvehousing secured to the inside of the cover member, a valve plunger inthe housing having a valve seat on the upper end thereof and beingspring-biased upwardly against the gasket, the valve plunger having anupwardly opening socket confined by the valve seat, the gasket beingsandwiched between the valve housing and the cover member and having acentral passageway therethrough aligned with the central passageway inthe cover member, the socket being axially aligned with the passageways,the stem slidingly and sealingly passing through the central passagewaysinto the socket and engaged therein and having its exterior wallsealingly engaged in said socket, means communicating between theinterior of the valve housing over the valve seat and the hollow bore ofthe stem, the lower end of the stem that is engaged in the socket beingimperforate but for an axial end opening, the plunger having axiallyextending channel means on the interior of the socket opening at theupper end thereof adjacent the valve seat and extending to the bottom ofthe socket and the stem having a shoulder cooperating with the valveplunger to space the lower end of the stem above the bottom of thesocket, said shoulder having an outer diameter greater than the innerdiameter of said socket and that portion of the stem which engages insaid socket, the shoulder engaging against the portion of the plungerthat surrounds the entrance to the socket to define metering entrancemeans in cooperation with the upper end of said channel means, the axiallength of the portion of the stem which engages in the socket being lessthan the axial length of the socket, to provide clear passage for thepressurized product from the bottom end of the channel means to saidaxial end opening when said stem is engaged in said socket.
 3. channelmeans in the interior of the socket in said wall extending generallyaxially of the cylindrical wall, opening at the upper end thereofadjacent the valve seat and opening at the bottom end adjacent saidfloor, E. a sprayhead including an exterior movable button having anexternal orifice and a hollow cylindrical stem, said stem having anupper and a lower portion, the upper portion of the stem passing throughthe passageway of the elastomeric gasket in a sealing and sidingengagement, said upper portion having an external diameter slightlygreater than the internal diameter of the socket wall, the lower stemportion telescopically and sealingly engaged in said socket, said lowerportion being of slightly smaller diameter than the upper stem portionto form a shoulder, said shoulder engaging against the portion of theplunger surrounding the entrance to the socket to define meteringentrance means in cooperation with the upper end of said channel means,and the lower stem portion having an axial end opening spaced away fromthe center post providing the only entrance to the interior of thehollow stem from the bottom end thereof and said lower portion having alength less than the depth of the socket, and F. whereby the bottom ofthe upper stem portion engages the internal socket wall to establish apressurized product flow path from the housing during actuation of thepackage, said path extending over said valve seat down through thechannel means, between the floor and the bottom end of the stem and thenup through the axial opening in the stem between the internal wall ofthe stem and the post.
 4. The valve assembly as claimed in claim 3 inwhich the plunger has a gallery at the upper entrance of the socketbelow said valve seat into which gallery said channel means at the upperend thereof open.
 5. The valve assembly as claimed in claim 3 in whichthe shoulder is engaged on said valve seat into which valve seat saidchannel means at the upper end thereof open.